Switch mechanism for controlling circuits of high current value.



G. E. PALMER.

SWITCH MECHANISM FOR CONTROLLING CIRCUITS OF HIGH CURRENT VALUE.

APPLICATION FILED FEB- 8, I915- RENEWED FEB-23,1916.

Patented Apr. 18, 1916.

4 SHEETS-SHEET 1.

ffimavvavw ZZiaeaaea G. E. PALMER.

SWITCH MECHANISM FOR CONTROLLING CIRCUITS OF HIGH CURRENT VALUE. APPLICATION FILED FEB. 8. I915- RENEWED FEB. 23, I916.

1,179,957 Patented Apr. 18,1916.

4 SHEETS-SHEET 2.

G. E. PALMER.

SWITCH MECHANISM FOR CONTROLLING CIRCUITS OF HIGH CURRENT VALUE.

APPLICATION FILED FEB. 8. I915- RENEWED FEB. 23,1916.

1,179,957. Patented Apr. 18, 1916.

4 SHEETSSHEET 3.

zi imeafiea' Jame 1- G. E. PALMER.

SWITCH MECHANISM FOR CONTROLLING CIRCUITS OF HIGH CURRENT VALUE. APPLICATION FILED FEB. 8, 1915. RENEWED FEB. 23. I916.

1,179,957. I Patented Apr. 18,1916. 2 59 4 SHEETSSHEET 4.

UNITED PTENT FFIC.

GRANVILLEE. PALMEE, OF NEWTON, MASSACHUSETTS, ASSIGNOR TO THE PALMER ELECTRIC & MANUFACTURING COMPANY, OF BOSTON, MASSACHUSETTS, .A, CORPO- RATION OF 'MAINE.

SWITCH MECHANISM FOR CONTROLLING CIRCUITS OF HIGH CURRENT VALUE.

Specification of Letters Patent.

Patented Apr. 18, 1916.

Application filed February 8, 1915, Serial No. 6,868. Renewed February 23, 1916. Serial No. 80,086.

To all whom it may concern:

Be it known that I, GRANVILLE E. PALMER, a citizen of the United States, and a resident of Newton, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Switch Mechanism for Controlling Circuits of High Current Value, of which the following is a specification.

This invention has relation to what I may term repeater switches, by means of which circuits carrying a current of relatively high value may be controlled by a circuit of relatively low current value, such for instance as may be used in fire alarms or like signal systems.

Generally speaking, the object of the invention is to provide a switch mechanism which may be used in a normally closed controlling circuit, the opening 'of which causes the operation of a switch controlling a working circuit of high current value, and in which theconsumption of energy in the normally closed controlling circuit is relamatic view illustrating the circuits.

tively low.

Another object of the particular embodiment of the invention hereinafter described is to provide certain improvements in the construction and arrangement of the parts of the. switch mechanism, so that the main switch is locked by mechanical locking means, and is opened when electromagnetically controlled mechanism is actuated.

The invention has further for its object to provide various other improvements in the construction and arrangement of the switch mechanism which I will explain in detail in the following specification and point out in the appended claims.

On the accompanying drawings,Figure 1 illustrates in front elevation a switch mechanism per 86, embodying the invention. Fig. 2 represents a side elevation of the same. Fig. 3 represents a longitudinal vertical section through the center of the.

switch mechanism; Fig. 4 is a diagrii n- 1g. 5 illustrates a switch mechanism for closing different sources of potential through the Fig. is a diagrammatic view representing the clrcuits of the switch mechanisms last referred to. Fig. 7 illustrates a device arranged between the switch mechanisms for preventing the closing of one until the other is fully opened, and vice versa. Fig. 8 re resents a section on the line 88 of Fig.

I will first explain the mechanical features of construction and arrangement of the switch mechanism, which I have selected as one embodiment of the invention.

angle. Cooperating with the stationary contacts are the two pairs of movable laminated brush contacting members 16, 17, secured to a cross bar 18 and movable about the axis of the shaft 19, as will be subsequently explained. The two members 16 and 17 are arranged at right angles to each other as shown, the ends'of the laminae being beveled to engage the contact surfaces l4 and 15 of the stationary contacts.

On the diagram shown in Fig. 4;, for convenience the two pairs of movable contact members 16, 17 are conventionally indicated at a a and the stationary contacts are indicated at b b. The cross bar 18 is secured to the lever 20 which is mounted on the rock shaft and which may be swung between the full line and dotted positions shown in Fig. 3. In its full-line position, the main switch members 16 and 17 are in contact with the corresponding stationary contacts. The rock shaft is mounted in the side walls of a main casting, as indicated generally at 21, and which is secured to the plate 11. The lever 20 is moved to closed position, that is into position to close the main switch, by an electro-magnet, but it is held in closed position by mechanical meansg which may be electro-magnetically trippeduto release the lever and permit it to move to open position. The opening of the lever and the main switch is accomplished bysprings indicated at 22 coiled about the shaft 19, each having one, end, engaged with the lever '20 and its other end bearing against a shaft 23, the function of which will be subsequently explained.

For closing the lever 20 and the main switch, I utilize a solenoid magnet 24 with which coiiperates a movable armature or plunger 25 pivoted by the pin 26 to the lever 20. At its upper free end the lever 20 carried a latch 27 which is pivoted thereto by the pintle 28. This latch is approximately triangular, as shown, and it is provided with a notch 29 below the pintle adapted to register with a catch bar 30 supported by the forwardly projecting recessed arm 31 of the main casting 21. \Vhen the lever 20 is moved from the dotted position to the fullline position, the end of the latch 27 rides up over the catch 30 until the notch registers therewith so as to permit the latch to drop into the full-line position shown in Fig. 3. If at this time the latch were un-. restrained, the tension of the springs 22 upon the lever 20 would move it back to the dotted position. Hence, for the purpose of holding the latch in engagement with the catch 30, I provide what I may term a locking dog which consists of a plate 32 having ears 33 pivoted upon the cross-pin 34 secured in the main casting. This dog is free to swing upon the pivot 34, so that, as the latch 27 rides over the catch 30 in the closing movement of the lever 20, the dog 32 will be swung about the pivot 34 by the engagement of the small end of the latch therewith the catch 30, whereupon the locking dog 32 will immediately swing back into position as shown in Fig. 3, so as to rest upon the top of and lock the latch in engagement with the catch. Therefore the locking dog, the latch and the catch constitute mechanical means for holding the main switch in its closed position, and they will so hold the main switch until thelocking dog is moved to release the latch. The latch-releasing mechanism includes an electro-magnet 35 at the upper end of the switch mechanism and an armature 36 therefor which is carried by arms 37 pivoted upon the pivot or pintle 34. One of these arms 37 is formed or provided with a right-angle arm 38 which lies in front of and close to the locking dog 32, so that, in the particular embodiment of the invention selected for illustration, whenfthe electro-magnet 35 is energized and the armature 36 is raised so as to rock the arms 37 about the pintle 34, the arm 38 will engage the locking dog 32 and move it to the left so as to release the latch 27 and permit the lever 20 to open under the influence of the springs 22. In order that the locking dog 32 may '1 be actuated manually, one of the levers 37 is provided with a forwardly'projecting finger 39 which may be operated at will. The main casting 20 is so formed as to provide a casing 40 which incloses the magnet 36, the locking dog and the releasing mechanism therefor, said casing being provided with an aperture 41 through which the end of the latch may pass and with an aperture 42 for the manually-operated finger 39. Assuming that the main lever 20 has been moved to closed position and that the latch is engaged by the locking dog, the main switch will remain closed so long as the electro magnet 35 is deenergized. The electro-magnet 35 is located in what I term the control circuit, whereas the electro-magnet 24, to which I have previously referred, is energized by current derived from the high current value circuit as I will subscquently explain.

In order to close the circuit through the main switch-closing magnet 24, I employ a supplemental switch which is automatically operated by the movements of the main switch-carrying lever 20. This supplemental switch comprises two yielding contacts 43 and a movable member 44 carrying a contact 53. The member 44 consists of a lever loosely pivoted on the shaft 19 and which is adapted to play between two stops 45 and 46 carried by the lever 20. The stop 46 is formed on a bent plate 47 secured to the main switch 20 a little distance below the pivot 19, as shown in Fig. 3. The switch member 44 is normally pressed against the stop 46 by a spring 48; and it is provided with a shorter arm 49 which is shouldered to form a catch to be engaged by the hooked latch 50 which is pivoted loosely upon the pintle or shaft 23. This latch i pressed toward the end 51 of the stop plate 47 by a spring 52. When the lever 20 moves from the full-line position in Fig. 3 toward the dotted line position, the stop 46 moves inwardly and upwardly, carrying with it the supplemental switch member 44 about the axis of the shaft 19 so that the arm 49 swings downwardly, and at the same time the end 51 of the member 47 swings to the left so as .to permit the hooked latch 50 to swing to the left until it engages the catch on the end of the member 44. During this move ment, the switch member 44 is moved into position by the stop 46 so as to engage the stationary member 43, and, as soon as this happens, the hooked latch 50 engages the catch on the member 44 and locks it in position to close the circuit through the contact 43, and this, as will be subsequently explained, closes a shunt circuit through the main switch-closing magnet 24. These parts are indicated by the same numerals in the diagrammatic VlPW in Fig. 4.

hen the main lever 20 is moved from dotted position toward the left, the following action takes place. The stop 46 moves away from the member 44 which is held in circuit-closing position by the hooked latch 50, notwithstanding the pressure of the spring 48. The member 44 continues to be locked until the main lever has reached the full-line position, at which point the end 51 of the plate 47 engages the hooked latch 50. The continued movement of the lever 20 to the left, until the cross-bar 18 engages or nearly engages the main casting 21, then causes the part 51 to thrust the latch away from engagement with the member 44 so as to release the latter and permit the spring 48 to carry the contact 53 away from the contacts 43 and open the shunt circuit through the main switch-closing magnet. This further inward movement of the lever 20is permitted by the latch 27 on the upper end of the lever 20, said latch having a depending portion 54 adjacent the notch 29 so as to prevent possible disengagement of the latch and the catch during the final movement of the switch-carrying lever to the left. movement to the leftand the opening of the supplemental switch, the springs 22 carry the switch-carrying lever 20 in the reverse direction a sufficient distance until it is stopped in the full-line position in Fig. 3 by the engagement of the latch 27 with the locking dog 32. In order to close the shunt circuit through the magnet 24, it is necessary to close another contactor switch. This switch comprises amovable member 55 and two stationary members 56. The movable member 55 .is secured to the arm 37,

which I have previously explained, as shown in Fig. 3. When the armature 36 is lifted by the magnet 35, the member 55 is moved away from the stationary contacts 56 so as to open the shunt circuit through the switch-closing magnet 24, but, upon the failure of the current through the magnet 35, the armature 36 is released and the contact member 55 drops into engagement with the stationary contacts 56 so as to partially close the circuit through the magnet 24.

From the foregoing it will be seen that, in order to energize the magnet 24, it is necessary to close the supplemental switch 53, 43, and also the contactor switch 55, 56. Inasmuch as the switch member drops upon the stationary members 56, I provide means for preventing their disengagement through shock due to the closing of the main switch, and to this end I use an electromagnet 57 placed in the switch-closing shunt circuit, and an armature 58 secured to the movable member 55.

As a further matter of convenience of construction, a suitable fuse 59 is included in the shunt circuit which includes the main switch-closing magnet 24, said fuse being 'located in the spring clips 60, 60 on the insulating block 61 which closes the lower end of the casing formed by the main casting 21.

At the completion of the final It is unnecessary to describe in detail the various insulating blocks, connecting screws, the wiring and the like, with which the switch mechanism which I have just described is equipped.

I will now explain the operation of the switch mechanism, reference being also had to Fig. 4 which illustrates diagrammatically the several circuits. In this last-mentioned figure, I have illustrated what I term a controlling circuit which receives its current from a source of potential of low-current value, as for instance a storage battery. This circuit comprises the conductors 0 and (Z. Arranged in multiple therewith is a circuit indicated at e and which includes the electro-magnet for controlling the operation of the releasing mechanism for the locking dog This circuit is normally closed but it may be opened by a key f or by a mercury-contact thermostat indicated asa whole by 9 arranged in a shunt circuit 71 In lieu of these devices for opening and closing the circuit 6, any other suitable appliances may be employed and they may be operated either manually or automatically as desired. The main working or load circuit, which is connected with a source of potential for supplying a current of high value say for instance 500 volts, is indicated at i, i, and connected in multiple therewith is the circuit jj which includes the main switches a Z) for the working circuit, and also any devices which are to be operated or energized by current through said circuit, such as exemplified by an electro-magnetic alarm bell is. A. shunt circuit m, which may be opened and closed by a manually operated switch 01, is arranged in multiple with the circuit j and includes the fuse 59,

' the contactor switch 55, 56, 56, the electromagnet 57, the main switch-closing magnet 24,'and the supplemental switch 53, 43, 43. As I have already stated, the circuit a is normally closed so that the electro-magnet 35 is likewise normally energized. Upon the failure of current in the circuit a, by the operation of the thermostat g, by open"- ing the key f, or from any other cause, the electro-magnet 35 is deenergized and is permitted to drop its armature, whereupon the contactor switch 55, 56, 56 of the shunt circuit m is closed.

It will be remembered that, when the main switch is open, the contact on the supple mental switch member 44 is in engagement with the stationary contacts 43, so that, as soon as the contactor switch is closed. the shunt circuit on is completely closed so as to derive its current from the main source of potential of high current value. T hereupon, the coil 57 is energized so as to exert a pull upon the switch member 55 and hold it securely from being displaced from the stationary contacts 56. At the same time,

\ dog to swing down into interlocking position. The continued movement of the main switch lever to the left from the vertical position then causes the member 51 to disengage the hooked latch 50from the catch on the member 1 1 and permit the supplemental switch member to open, thereupon breaking the shunt circuit m but leaving the main switches and the main working circuit j closed, and locked by the mechanical locking mechanism. The parts will remain in this position so long as the controller circuit e-is open. Upon the closing of the circuit 6, the coil of the magnet 35, responsive to current restoration, is energized and lifts the armature 36 to operate the release mechanism to move the dog 32 into position to release the latch 27, whereupon the springs 22 throw the main switch-carrying lever 20 toward open or dotted position, thereby opening the main switches a b so as to open the circuit and closing the supplemental switch 53, 43. 'The parts will then remain in this position until the current fails in the controlling circuit 6.

. It is evident that, in lieu of using a controlling circuit of low current value for controlling the operation of the releasing mechanism for the latch 27, I may arrange the switch mechanism as illustrated in Figs. 5 and 6 so as to supply a working circuit with current from either of two sources of potential in case current in the other fails; that is, I may supply to a working circuit direct current from one source of potential,

' and alternating current from another source of potential, and so arrange the switch mechanisms that one will not supply current to the working circuit until the other switch mechanism has been fully opened. In this arrangement, the two switch mechanisms, which in Fig. 5 is indicated at 100 and 101, are precisely similar to the one illustrated in Figs. 1, 2 and 3, which I have already described, except that to the two main switch-carrying levers" 20, 20, there are connected shafts 102, 103 (which may be extensions of the shafts 19) which are axially alined with the axis of movement of said levers. These two shafts, which are independent of each other, are arranged with their ends close together as shown in Fig. 8. These shafts project into a frame comprising side walls 104, the base flanges of which may be secured upon the base 105 upon from the other disk.

which the switch mechanisms are mounted. Pinned upon the two shafts are the two ratchet disks or members 106, 107, which have the ratchet teeth 108, 109, respectively. For engagement with the disks there are two hooked latches, one at 110 for engaging the tooth 109 on the disk 107, and the other at 111 for engaging the tooth 108 on the disk 106. These two hooked latches are pivoted upon the shafts 112, 113, respectively, and are moved toward their respective disks or members by the springs 114, 115. Each disk carries an arm or member for disengaging the corresponding latch To this end, the two hooked latches are formed with the elbow arms 116, 117, respectively. The disk 106 has a laterally extending arm or member 118' provided with an adjustable screw 119 for engaging the arm 116 of the hooked latch 110 so as to disengage it from the tooth 109. The disk 107 likewise has a laterally extending arm or member 120 carrying an adjusting screw 121 for engaging the arm 117 of hooked latch 111 to disengage it from the tooth 108 on disk 106. These parts are all arranged relatively so that the movement of the disk'107, due to the opening movement of the main switch lever 20 of the switch mechanism 101, will ;not cause the engagement of the screw 121 with the arm 117 so as to release the hooked latch 111 from the tooth 108 until the said main lever 20 has nearly completed its opening movement, whereupon the final movement of the disk 107 will cause the latch 111 to be fully disengaged from the tooth 108 so as to release the disk 106 and permit the shaft 102 to be rocked in the opposite direction by the closing of the main switch mechanism 100. As the disk 107 reaches the limit of its movement in the direction of the arrow, as shown in Fig. 7, the tooth 109 registers with the hooked latch 110, so that, when the disk 106 moves in the direction of the arrow thereon so as to carry the screw 119 away from the arm 116, the hooked latch 110 will engage the tooth 109 and thereafter lock the disk 107 and the shaft 103 against further movement, with the main switch lever 20 of the switch mechanism 101 in its fully open position. The said lever 20 cannot thereafter be closed to close the switch mechanism 101 until the main switch-carrying lever 20 of the switch mechanism 100 has been released and has reached fully open position. Thus, when one switch mechanism is closed, it looks the other in open position, and vice versa.

In Fig. 6, I have illustrated diagrammatically the arrangement of circuits 1 for the mechanism shown in Fig. 5. 0, 0 indicates an electric circuit which receives direct current of high value from a suitable source of potential, and p, p indicates a circuit for receiving alternating current of high value from another source of potential. 9, g indicates the working circuit, to which current may be supplied from either the circuit 0, 0 or the circuit p, p. The magnet 24., for closing the main switches a, I) of the circuit 0, 0,

is included in a shunt circuit 1", said shunt circuit. also including the supplemental switch 53, 43, the coil 57, and the contactor switch 55', 56. These parts are all duplicated in the switch mechanism 101 for the circuit p, p, except that the shunt circuit is indicated at s so that it may be easily followed on the diagrammatic drawing. A shunt control circuit, in multiple with the circuit 0, 0 and which is indicated at t, includes the electro-magnet 35 for the switch mechanism 101, and similarly a shunt control circuit u, u in multiple with the alternating current circuit p, 72 includes the magnet 35 of the switch mechanism 100, as will be readily understood from the diagram. It maybe assumed that in this mechanism, under the conditions illustrated, current is being supplied to the working circuit 9, g from the alternating current circuit 19, p, in which the switches a, Z) of switch mechanism 101 are closed. Upon failure of the current in circuit p, p for any cause, as by opening a key'or separating the contacts of a thermostat or the like, or because of a short circuit, or other cause', the magnet 35 of the switch mechanism 100 in circuit to, u is deenergized, the circuit 1 will be closed, and the electro-magnet 24: of switch mechanism 100 will close the main switch a, Z) of circuit 0 so as to throw the direct current on the working circuit. This cannot occur, however, until on the closing ofthe contactor switch 55, 56, the electro-magnet 35 of the switch mechanism 101 is energized to release the latch of such switch mechanism and permit themain switch-carrying lever 20 thereof to open. As the said lever 20 moves to open'positio-n, it rocks the shaft 103, carrying with it the disk 107, which, as it nears the completion of its movement, disengages the latch 111 from the disk 106. This happens just as the main switch lever 20 of the switch mechanism 101 reaches its fully open position. Thereupon, since the electro-magnet 24 of switch mechanism 100 is energized, the main switch a, b of circuit 0, o is closed to supply direct current to the working circuit g. The main switches a, b of the alternating circuit are now open. When the current is subsequently restored to circuit 39, p, the branch circuit u, 14 through the magnet 35 of switch mechanism 100 is closed so as to release the latch of said last-mentioned mechanism and at the same time to open the circuit through the magnet 35 of switch mechanism 101. Thereupon, the main switch a, b of the switch mechanism 100 is opened to break or open the circuit 0, 0, and thereafter to close the circuit p, p and again supply alternating current to the working circuit 9, g. In this connection, it will be observed that the circuit 6 includes both of the stationary contacts 56 of the contactor switch of the main switch mechanism 100 so that current for the circuit t is, derived through a portion of the circuit' r.

In the last-described construction and arrangements of parts, the'lcircuits 0, 0 and t may be regarded as the controlling circuit It will be apparent to those skilled in the art that, by means of the construction and arrangements of parts which I have herein described, certain important advantages may be obtained. The magnet 35 in the control circuit has merely the function of raising and releasing the armature 36 to which is connected the arm 37, and the contactor switch member 56, and, as these parts are light and are in part supported by the pivot 34:, the current consumption in the coils of magnet 35 is inappreciable. Again, the electro-magnet 24: for closing the main switch is energized only long enough to close said switch, for the closing movement thereof interrupts the current through said magnet by opening the supplemental switch.

Thereafter the main switch is held in closed locking dog to release the locking mechanism and permits the main switch automatically to be opened by the springs 22. An advantageous result, which is secured by the cotiperating and releasing devices by which the main switch of one switch mechanism controls the operation of the main switch of the other mechanism, is that, by the employment of the latches and pawls and the arms carried by the ratchet disks, I am enabled to prevent any mechanical frictional resistance to the free operation of the shafts and their connected main switches. Said devices are simple and their operation is mechanically effected.

The switch mechanism per se lends itself to many uses and is particularly adapted for controlling circuits of high current value, say from 500 to 1,000 volts without causing the formation of destructive arcs. In one aspect, the switch mechanism operates as a reverse relay 0r repeater in that the closing of the working circuit is caused by current failure in the control circuit.

Having thus explained the nature of my said invention and described a way of making and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, what I claim is 1. The combination with a working circuit deriving its current from a source of potential, and a main self-opening switch therefor, a shunt circuit including a contactor switch, and also an electro-magnet for closing the main switch, a locking mechanism mechanically operated to lock the main switch in closed position, and a control circuit deriving its current from a separate source of potential and including electromagnetically controlled means for simultaneously unlocking said locking mechanism and opening the contactor switch in the shunt circuit.

2. The combination of a working circuit,

I a self-opening main switch therefor, a

normally closed control circuit, a normally open shunt circuit from the working circuit including electro-magnetic means responsive to current therein for closing the main switch and also including a normally open contactor switch, locking means moved mechanically to operative position to hold the main switch in closed position, and electro-magnetic means included in the control circuit and responsive to current failure therein for automatically closing the contactor switch and responsive to current reposition,

storation to automatically open said contactor switch and release the locking mechanism, whereby said main switch automatically opens.

3. A switch mechanism comprising a main switch for closing a working circuit, a lever for operating said main switch, an electromagnet adapted to be energized by current in a shunt circuit from the main circuit for moving said lever to close said main switch, mechanical means for opening sald switch, a stationary catch, a latch carried by said lever for engaging said catch, a locking mechanism constructed and arranged to operate mechanically to lock the latch on said catch when said lever is in switch-closing and electro-magnetic means, adapted to be energized by a control circuit, and constructed and arranged to move said looking dog to inactive position thereby to release the latch and permit the main switch to open.

4. A switch mechanism comprising a main switch for closing a working circuit, a lever for operating said switch, yielding means for mechanically opening said switch, me

chanical means for mechanically locking said lever in switch-closing position, electromagnetic means adapted to be included in a shunt circuit from the working circuit and constructed and arranged to move said lever I to switch-closing position, a supplemental switch adapted to be included in said shunt circuit, mechanism operated by said lever for closing said supplemental switch when the lever is in switch-opening position, a contactor switch, for said shunt circuit, and electro-magnetic means responsive to current in a control circuit for releasing said locking means and for opening the contactor switch.

5. A switch mechanism comprising a main switch for closing a working circuit, a lever for operating said switch, yielding means for mechanically opening said switch, mechanical means for mechanically locking said lever in switch-closing position, electromagnetic means adapted to be included in a shunt circuit from the working circuit and constructed and arranged to move said lever to switch-closing position, a supplemental switch adapted to be included in said shunt circuit, mechanism operated by said lever for closing said supplemental switch when the lever is in switch-opening position, a contactor switch for said shunt circuit, and electro-magnetic means adapted to be included in a control circuit and responsive to current failure for closing said contactor switch.

6. A switch mechanism comprising a main switch for closing a working circuit, automatic mechanical locking mechanism for mechanically locking said switch in closed position, yielding means for opening the swltch when released by the locking means, operative means including an electro-magnet and constructed and arranged to close said switch, a supplemental switch and a contactor switch in series with said electro-magnet, mechanism constructed and arranged to be actuated by said operative means for closing said supplemental switch when the main switch is open and opening said supplemental switch when the main switch is closed,

and electro-magnetic means, adapted to be operated by the failure of current in the control circuit, for closing the contactor switch.

7 A switch mechanism comprising a main switch for closing a working circuit, automatic mechanical lockin mechanism for mechanically locking said switch in position, yielding means for opening the switch when released by the locking means, operative means including an electro-magnet and constructed and arranged to close said switch, and electro-magnetie means rendered operative by current to release said locking mechanism, and rendered operative by current failure to close a circuit through said electro-magnet.

imes? 8. A switch mechanism comprising a switch, electro-magnetic mechanism to close said switch, mechanical means to lock the switch closed, and electro-magnetically con-- trolled mechanism constructed and arranged, when the electro-magnet thereof is energized, to operate the mechanical means to release the switch, and, when the said electromagnet thereof is denergized, to complete a circuit through the electro-magnetic switch-closing mechanism.

9. A switch mechanism comprising a main switch adapted to close a working circuit, yielding means for opening said switch, locking means for mechanically holding saidswitch' in closed position, electromagnetic mechanism, conditioned for operation when the coil thereof is energized, to close the main switch, electro-magnetic means constructed and arranged when energized to release said locking mechanism, and when deenergized to condition said switch-closing electro-mag'netic mechanism for operation, and a supplemental switch adapted to be electrically connected with the energizing coils of said switch closing mechanism, and constructed and arranged to be closed when said main switch is open and opened when, said main switch is closed.

10. A switch mechanism comprising a main switch, a movable member operatively connected to said switch, a stationary catch, a notched latch pivoted to the said member and adapted to coact with said catch to lock the switch closed, a locking dog for holding the latch on said catch, and means for moving said dog to release the catch.

11. A switch mechanism comprising a .main switch, a movable member operatively connected to said switch, a stationary catch, a latch pivoted to said movable member and arranged to ride over and engage said catch, a pivoted locking dog arranged to swing into engagement with the free 'end of said latch and hold it in locked engagement with said catch, and electromagnetic means for controlling said locking dog.

12. A switch mechanism comprising a main switch, a movable member operatively connected to said switch for opening and closing it, a stationary catch, a notched lever pivoted to said member adapted to coact with said catch, a pivoted locking dog arranged to engage said latch and hold it on said catch, an electromagnet adapted to be placed in a control circuit, an armature therefor, and means by which the movement of said armature moves the said dog to latch releasing position 13. A switch mechanism comprising a main switch, yielding means for opening the switch, electro-magnetic means, including an electro-magnet and a lever, connected .to the armature or plunger thereof, for closing said switch, a stationary catch, a notched latch pivoted, to said lever and adapted to coact with said catch, a pivoted locking dog for holding the latch on said catch, and electro-magnetio means for moving said dog to release said catch.

14. A switch mechanism comprising a main switch, yielding means for opening the switch, electro-magnetic means, including an electro-magnet and a lever, connected to the armature or plunger thereof, for closing said switch, a stationary catch, a notched latch pivoted to said lever and adapted to 00- act with said catch, a pivoted locking dog for holding the latch on said catch, an electro-magnet adapted to be placed in a control circuit, an armature therefor, and a pivoted arm connected to said armature and having means for moving said dog to latch-releasing position.

15. A switch mechanism comprising a main switch; an electro-magnet switch-closing mechanism including an electro-magnet, an armature or plunger, and a lever connected thereto, and operatively connected to the movable members of said main switch; a supplemental switch adapted when closed to close a circuit through said electro-magnet, and including stationary and movable contacts, and a pivoted arm carrying the lastmentioned movable contact; separated stops on said lever for moving said arm to open and closed positions to open and close said supplemental switch; a spring-tensioned latch for locking said arm in the closed position; and means operated by said lever and onstructed and arranged to release the latch when said main switch is closed.

16. The combination with two circuits deriving their currents from separate sources of potential and each adapted to supply current to a working circuit upon failure of current in the other; of switch mechanisms for said first-mentioned circuits, each switch mechanism comprising a main switch, an electromagnetic means responsive to cur rent in the circuit controlled by said main switch for closing the main switch, and a locking mechanism for locking the said main switch in closed position; and an electro-magnetic device in each switch mechanism included in a shunt circuit connected with the circuit controlled by the other switch mechanism and responsive to current to release said locking mechanism.

17 lhe combination with two circuits de- 120 riving their currents from separate sources of potential and each adapted to supply current to a working circuit upon failure of current in the other; of switch mechanisms for said first-mentioned circuits, each 125 switch mechanism comprising a main switch, an electro-magnetic means responsive to current in the circuit controlled by said main switch for closing the main switch, and a locking mechanism for locking the said main switch in closed position; an electromagnetic device in each switch mechanism included in a shunt circuit connected with the circuit controlled by the other switch mechanism and responsive to current to release said locking mechanism, rock shafts connected to the main switchclosing means of said switch mechanisms, and means controlled by each shaft for locking the other shaft and the associated main switch in open position when the firstmentioned shaft and the main switch connected thereto is not in open position.

18. The combination with two circuits deriving their currents from different sources of potential; of switch mechanisms for said circuits each comprising a main switch and 'rock shafts connected thereto, each switch mechanism also including electro-magnetic means responsive to current derived from the circuit controlled thereby for closing the associated main switch; and means 0perated by each rock shaft for locking the other against movement, when the switch associated with such first-mentioned shaft is not in open position.

19. The combination with two circuits deriving their currents from different sources of potential; of switch mechanisms for said circuit comprising main switches and rock shafts connected thereto, each switch mechanism also including means for closing the associated main switch; and means operated by each rock shaft for locking the other against movement, when the switch associated with such first-mentioned shaft is not in open position, said last-mentioned means comprising a ratchet member secured to each shaft, a latch 0r pawl for locking each member, and means movable for each member for releasing the latch of the other member.

20. The combination with two circuits deriving their currents from separate sources of current and each adapted to supply current to a working circuit upon failure of current in the other; of switch mechanisms for said first-mentioned circuits, each switch mechanism comprising a main switch, an electromagnetic means responsive to current in the circuit controlled by said main switch for closing the main switch and provided with a lever connected thereto, a locking mechanism for locking the said lever when said main switch is closed; and a contactor switch for closing the circuit through the coils of said electromagnetic main switch-closing means; and an electro-magnetic device in each switch mechanism connected in multiple with the circuit controlled by the other switch mechanism, and responsive to failure of current therein for closing the said contactor switch of said first-mentioned switch mechanism.

21. The combination with two circuits deriving their currents from separate sources of potential and each adapted to supply current to a working circuit upon failure of current in the other; of switch mechanisms for said first-mentioned circuits, each switch mechanism comprising a main switch, an electromagnetic means responsive to current in the circuit controlled by said main switch for closing the main switch and provided with a lever connected thereto, a locking mechanism for locking the said lever when said main switch is closed; and a contactor switch for closing the circuit through the coils of said electro-magnetic main switch-closing means; and an electromagnetic device in each switch mechanism connected in multiple with the circuit controlled by the other switch mechanism, and responsive to failure of current therein for closing the said contactor switch of said first-mentioned switch mechanism and responsive to current therein to release the locking mechanism of said first-mentioned switch mechanism.

In testimony whereof I have aflixed my signature, in presence of two witnesses.

GRANVILLE E. PALMER.

Witnesses MARCUS B. MAY, P. W. PEZZETTI. 

